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fish that are compabile with octopuses


Apr 19, 2003
It seems to me that if one purchased herbivorous fish that were roughly the same size as an octopus, that the fish and the octopus could live in the same tank without predating on each other. Has anyone done this in the past?

I now have a beautiful pair of yellow headed sleeper gobys, along with a fairy wrasse, in my octopus tank. Any idea whether adding an octopus would be a mistake?

The octopuses I've received from FishSuply are roughly 18" tentacle tip to tip, with bodies perhaps like a 2.5" ball. The fish are all 2.5" or larger. I'm assuming that an octopus would only attack food that was quite a bit smaller than it was (or am I being naive).

A tad on the naive side me thinks :smile: lol

to be fair jimbo keeps fish with his octos and i have had shrimps outlive octos so whos to say? i just fear that it may be a snack for octos if hungry?
I hear so consistently that, depending on size, one is food for the other...that nearly all marine fish are omnivorous to some degree and will nip an octo if they're big enough. Yet I've found myself thinking along the same lines as you, Jon, that surely some fish are herbivorous enough to not be an octo-threat. We aquarists can be such a conservative bunch, I suspect it may be that since the vast majority of the time octos and fish don't mix, we've written off the concept altogether.

I woudn't mind experimenting with this someday :madsci: , but I'm afraid not now...I'm working on only my second octo, and so for now will be as conservative as I can. If you're willing to risk fish/octo loss...maybe you should give it a shot? :? If "The Octopus Show" is any example, judging from what the GPO was able to take down (four foot sharks!) you'd definitely need an herbivorous fish MUCH larger than the octo.

Of course, perhaps I'm just denying reality... :P

I put a 2.5" blenny in with my octo a few days ago, figuring she would snap it up. Not so, the blenny seems to narrowly escape her attacks each time. The blenny is quite territorial and will come out and investigate just as much as the octo will. I would like it out but it'll probably be impossible with the live rock. I'm sure if it was a fancy colorful fish that I wanted to stay in there, she would have killed it the first day. :bonk:
I had a Star Damsel in with my first octopus Hermin. They cohabitated for about 4 months, till I'm assuming the fish got too comfortable and one day Hermin ate him!

So far I haven't wanted to put anything in with Ink except Serpent (serpent starfish). Ink still takes Serpent's food away from him everytime I feed, if Ink's hungry too! It really is comical to watch!

I keep small parrotfish and a goby with my Octopus cyanea, and they don't bother each other at all. My tanks are very large, however - 8 feet in diameter - so the fish have a lot of hiding spaces.
hi Gayla, would love to see pics of that set up especially since its a cyanea too!

Sideways -
yeah - I have two circular outdoor tanks that are on a covered lanai. i know - they're tanks, not aquaria - so i'm really cheating :oops: because I don't have to worry about tank chemistry, etc: the water's just pulled up from the lagoon. They are at the Hawaii Institute of Marine Biology. I wanted to answer about the herbivorous fish, though, since I was worried they'd "disappear" but they seem to do fine. I'm not sure why the octopuses don't bother them, especially since I don't feed them every day but about 4X a week.
I'll try to dig up pictures soon of the tanks and my critters.
Occy hunts with stealth

My friends dad has a tank (180 gal) were he attempts to make a food chain system. Everything was going fine (a little expencive if you ask me) but h enjoyed it. He decided to add a o. vul. it was very young and small so he assumed it would be eaten extreamly fast, but it hid and would come out at night, even tho it was one of the smaller preditors in the tank every night it raided the tank. With its night time stealth attacks on the clams and small fish it got fairly large, but it was eaten evenutaly. As far as fish picking on it, they were not too good at it, it was able to get into small areas and under area's the other larger preditory fish could not. It just got cought in a bad situation. I dought this would work with a smaller tank but with a large tank the octopus did put on a better show than any of the fish. It seemed to be able to sneek up on things and suprize them, as were the large fish just waited for the right moment.
I think you're right - the size of the tank and the availability of hiding places is likely to make a big difference. 8) Cool story ... I'll bet that was great to watch.
He has a buch of viedo tapes of the tank, he passed away not to long ago, so the tank aint doing as well anymore, but its still fun to watch the viedo tapes of the octo.

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